From -40F to +90F: From Ice Cores to Hurricanes

You might think that scientists know everything there is to know about the water cycle; after all, it is one of the fundamental concepts we learn about in science class as children. However, the water cycle is a complex system and scientists are still working to fully understand the role of water vapor: where it originates, how it moves through the atmosphere, and how it influences climate processes.

Water vapor, the most potent greenhouse gas, is closely tied to air temperature: every time the air temperature increases by 1 degree Celsius, the water vapor content in the air increases by 7%. As the water vapor in the air increases, the atmosphere becomes more dynamic and intensified, which is to say that wetter regions become wetter, drier regions become drier, and the potential for extreme events—such as hurricanes, snow storms, and heat waves—also increases.

It is this latter prospect—extreme events—that is of particular interest to many climatologists, as well as the re/insurance industry. To understand extreme weather events, scientists need to observe physical processes, such as the behavior of water vapor in the atmosphere, and understand what drives them.

Hans Christian Steen-Larsen, researcher at Laboratoire des Sciences du Climat et de l’Environnement in Paris, is one such scientist. In his quest to trace air masses and understand what controls the uptake of moisture Dr. Steen-Larsen has traveled to Iceland, Greenland, throughout Europe and—most recently—to Bermuda.

Working with Dr. Andrew Peters, Associate Scientist at BIOS, at the Tudor Hill Marine Atmospheric Observatory, Dr. Steen-Larsen is using a spectrometer to make real-time measurements of the atmosphere’s chemical composition. Through these measurements, he can determine the relative composition of water isotopes, which help him understand the physical processes that take place in the atmosphere.

Dr. Steen-Larsen was fortunate enough to have his equipment running when Hurricane Leslie passed by Bermuda in September of last year, resulting in what are believed to be the first set of such measurements taken ahead of and during hurricane conditions. Such measurements will provide key insights into the physical processes involved in hurricane formation, as well as future efforts to predict the evolution of hurricanes and improve the prediction of future storm trends.

As one might imagine, such insights and improvements are also of keen interest to the re/insurance community here in Bermuda, as well as abroad. Dr. Steen-Larsen notes, “It is cost efficient for these companies to be on the forefront of understanding how such findings might impact the field of risk assessment. Basic research can be used by decision-makers and the re/insurance industry, but we also need long-term monitoring and data sets—such as those at Tudor Hill Atmospheric Observatory —to inform the basic research.”